As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
NR 3 CYLINDER HAS A STUCK EXHAUST VALVE. UPON CYLINDER REMOVAL IT WAS FOUND THAT THE VALVE HEAD WAS MUSHROOMED AND THE ROCKER ARM WAS ALSO DAMAGED. THIS CAUSED CONCERN DUE TO THE FACT THAT THE CYLINDER ONLY HAD 174.1 TOTAL HOURS SINCE IT WAS PURCHASED NEW. CYLINDER WAS SENT FOR REPAIRS AND THEN INSTALLED BACK ON THE ENGINE. (K)